A report from the Department for Transport shows there were 2,262 fatalities and injuries in 2011 on 20mph roads in built-up areas — 24 per cent more than in 2010 when 1,827 were recorded.

That compares to a one per cent reduction in casualties on 30mph roads in built-up areas.

How many people died or were injured on roads with a 30 mph speed limit then? The Sun doesn’t say, but the official data is easy enough to find. In 2010, 127,377 people were killed or injured on a road with a 30 mph speed limit. In 2011, it was 125,494.

In other words, that “1% drop” corresponds to almost 2000 fewer people were injured on 30 mph roads, while 400 more people were injured on 20 mph roads. That is a net decrease of 1448 injuries/deaths.

Just looking at the number of injuries on 20 mph roads is not going to tell you about how effective 20 mph speed limits are. You have to compare them with other speed limits. Data about how many 20 mph zones there are is hard to find, which makes making sense of the Sun‘s data difficult, but it certainly looks like a lot of them have been springing up lately, so an increase in injuries is to be expected – if there are more roads, there will always be more accidents!

Studies of 20 mph zones consistently find that the same stretch of road will see fewer accidents and fewer injuries if the speed limit decreases from 30 mph to 20 mph, especially if this decrease is enforced by speed bumps and other traffic calming measures.

* Incidentally, far from being “controversial”, surveys consistently find around 74% in favour of 20 mph speed limits and just 12% against them.

For various largely uninteresting reasons, I’ve not blogged lately. But then I came across this article on The Guardian website today, a for-and-against piece about mitochondria donation with an “against” argument from Peter Saunders that veers from irrelevant to flat out wrong. Let’s get started!

To begin with, this is not about finding a cure. It is about preventing people with mitrochondrial disease being born. These new technologies, even if they work, will do nothing for the thousands of people already suffering from these diseases, or for those who will be born with it in the future.

Now, here’s the first dodgy argument, one that I’m almost tempted to call a dog-whistle. Mitochondrial donations are not about “preventing people with mitrochondrial disease being born“, they’re about “preventing people being born with mitrochondrial disease”. Just look at how moving that phrase “being born” a few words to the right changed a factual statement about the procedure into a non-sequitur about abortion.

It’s of course true that unfortunately, this procedure will do nothing to help people that already have mitochondrial diseases – removing a mutation from the body is perhaps the most impossible thing in all of medicine – but that’s no argument against the procedure.

Also, Saunders claims that there is no need for the procedure when egg donation is already possible. Bear this in mind; it’ll come up again later.

Will it work? This technology uses similar “nuclear transfer” techniques to those used in “therapeutic cloning” for embryonic stem cells – which has thus far failed to deliver, and animal-human cytoplasmic hybrids (“cybrids”). […] Yet cybrids are now a farcical footnote in history. They have not worked. Ironically, it was in that same act of parliament that provision for this new research was also made.

First of all, cybrids were legalised in 2008. 3-4 years is not that long a time in medical research, especially for research into slow-developing, long-term conditions like Alzheimers and Parkinsons. But I decided to have a look on Google Scholar, to see if cybrids were just a “farcical footnote”. Since 2008, there have been at least 362 papers about cytoplasmic hybrids, including 114 in the last year and a half or so. Some of these are papers exploring the ethics of the procedure, but an awful lot are detailing actual breakthroughs made using these cytoplasmic hybrids.

But even if he was telling the truth, and both fields had proved to be dead ends, this would still be irrelevant to mitochondrial donation. All it says is that mitochondrial donation uses one technique which is also used in stem cell research. As far as arguments go, this is up there with “vegetarians are evil because Hitler was a vegetarian”.

Is it safe? No. Each technique involves experimental reproductive cloning techniques and germline genetic engineering (that is, it affects the genes passed on to children) – both of which are highly controversial and potentially dangerous. Cloning by nuclear transfer has so far proved ineffective in humans and unsafe in other mammals with a large number of cloned individuals spontaneously aborting, and others suffering from physical abnormalities or limited lifespans.

Well, it’s good thing there’s no cloning involved with this technique, thus making that last sentence completely pointless scaremongering.

This is true, but the thing is: if a woman with a mitochondrial condition doesn’t use this technique and conceives a child naturally, there is a 100% guarantee that the mitochondrial defect will be passed to the future generation(s). The whole point of this method is to reduce the number of dangerous mutations being passed on.

Is it ethical? No. A large number of eggs will be needed, involving risky and invasive “harvesting” for women donors. How many debt-laden students or infertile women will be exploited by the offer of money, or free IVF treatment, in return for their eggs? How many embryos will be destroyed?

Ok, so, remember how earlier egg donation was a totally ethical alternative to mitochondrial donation? Well, with a deft sleight of hand Saunders is now claiming that egg donation is unethical!

There are concerns about paying people to donate body parts/fluids – it’s one of the most hotly discussed areas of bioethics – but in the UK, donors are not paid to donate eggs. They can have their travel and accommodation expenses paid (up to £750), but that’s it. There’s simply no room for the kind of exploitation Saunders worries about.

As far as I can tell, there is no difference to the egg donor between standard donation and mitochondria donation. The technique doesn’t necessarily require any extra eggs – though I suppose that depends on its success rate, which, since the technique is still experimental, no-one yet knows – and it doesn’t require any more embryo destruction that IVF or standard egg donation.

Then there are the issues of identity confusion for the children, who in effect will have three biological parents. Some mitochondrial diseases are much less serious than others. Once we have judged some affected babies not worthy of being conceived, where do we draw the line?

The mitochondria are, as the standard explanation goes, the little power stations that fuel each cell, and mitochondrial DNA has no effect on the wider body outside these power stations. A baby conceived by mitochondria donation is closer to having two parents than than a baby conceived by standard egg donation (since in mitochondria donation, all the DNA that affects what the baby actually looks like comes from the mother, not the donor), and if “identity confusion” is a concern, it’s odd that he’d endorse adoption either. And this technique does not mean any baby is “not worthy of being conceived” (unless he’s referring to the parents’ choice not to conceive naturally in the first place, in which case his argument is grosser and more unethical than I thought) – conception will still happen, it’s just that egg will be slightly modified first.

This debate is not being handled responsibly. The research scientists involved have financial and research-based vested interests, and getting the regulatory changes and research grants to continue and extend their work is dependent on them being able to sell their case to funders, the public and decision-makers.

I don’t think “I’m a research scientist and I want to continue my research” counts as a vested interest. It’s not like researchers are pretending their research isn’t dependent on this technique being allowed. I genuinely wonder how Saunders would prefer this debate be handled – he certainly never explains. Speaking of not handling debates responsibly, though neither Saunders nor The Guardian point this out, Saunders is the CEO of the Christian Medical Fellowship, a group that speaks out against a variety of medical techniques on religious grounds. As Mark Henderson said on Twitter, “Saunders makes many bad arguments vs mitochondrial transplants, omitting real reason he opposes: religion […] Nothing wrong with opposing embryo research for religious reasons, but those who do should admit it, and that no evidence would convince them”

Let’s concentrate on finding treatments and providing better support for affected individuals, rather than spending limited health resources on unethical, risky and highly uncertain hi-tech solutions that will most likely never deliver.

We already know that, no matter how difficult mitochondrial donation is, finding a cure for mitochondrial disorders is far far harder still – and perhaps impossible with our current knowledge of genetics. A human body contains billions of cells, each one containing at least one and often tens or hundreds of mitochondria. Replacing or fixing all of them would be far more difficult than replacing the mitochondria in a single cell; if you want an efficient way of spending limited health resources (really, limited research resources – the funding for this research would not be directly linked to the NHS), donation research is surely a better route to take.

(I intended to, for balance reasons, point out any inaccuracies in the response from the Nuffield bioethicist arguing for the procedure, but it already seems pretty sensible and fair. Quelle surprise…)

Edit: Also thanks to Mark Henderson for pointing out that the research is being carried out at Newcastle University and entirely publicly funded by the Wellcome Trust and the Medical Research Council – there are no vested business interests involved either.

Hey! I know it’s been a while since I blogged. Hopefully you haven’t missed me too much. Anyway.

Prunes are not a laxative, EU rules, says today’s Telegraph, endowing the EU with frankly godlike powers. Did someone in Brussels snap their fingers and magically prunes suddenly ceased to be laxatives?

Let’s help the Telegraph and suggest a more accurate headline. Perhaps…

Prunes are not a laxative, science suggested two years ago

The laxative effect of prunes is one of those things that “everyone knows”. Certainly MEP and frequent talking head Roger Helmer agrees, claiming:

“The euro is burning, the EU is falling apart and yet here they are: highly-paid, highly-pensioned officials worrying about the obvious qualities of water and trying to deny us the right to say what is patently true.”

Ignoring the fact that this study was carried out in mid-2009, before the Euro crisis kicked off, Roger Helmer has an interesting definition of “patently true”.

The study looked at the scientific evidence for the effectiveness specifically of dried prunes. There were two studies of the effectiveness of dried prunes in humans at the time:

Now, it’s possible that dried prunes are laxative – a much more recent study (albeit one funded by the “California Dried Plum Board”) from 2011 found that prunes appear to work better than the laxative psyllium at relieving constipation – but at the time this report was written, it simply would not have been accurate to say that, based on the body of available evidence, prunes were any better at keeping you “regular” than any other sort of fruit.

(The Telegraph also claims that the EU banned claiming that drinking water could prevent dehydration. Read the actual article, and the very last paragraph reveals that they’re talking about clincal dehydration, which is normally caused by disease rather than by not drinking enough fluids and that “This claim is trying to imply that there is something special about bottled water which is not a reasonable claim”)

“generate economic benefits of hundreds of millions of pounds through shorter journey times.”

Never mind the debates about safety and the environment, let’s look at this one argument. So, does a shorter journey equal a more economic journey? The problem is that cars need more fuel to travel faster, and so the faster you go, the worse your fuel efficiency is. Statistics that go right up to 80 mph are hard to find for some reason – the big US government study for example only went up to 75 mph – but according to the calculator at MPG for speed (better sources always appreciated), driving at 80 mph uses about 15% more fuel per mile than driving at 70 mph.

So, lets do some maths! For the sake of simplicity, we’ll assume every single journey on the motorways is work-related. The actual figures will be lower, especially on weekends and holidays.

At 70 mph, it takes 51 seconds to drive 1 mile. In this time, a car with a claimed “highway” fuel efficiency of 40 miles per gallon (roughly as efficient as a modern hatchback like a Ford Fiesta) will use about 0.11 litres of petrol. At the current average pump price, that’s 15 pence of petrol.

At 80 mph, you cover that same mile in 45 seconds, saving you 6 seconds. On the other hand, your car is now 15% less efficient. According to the calculator, your 40 MPG car is now doing just 28.8 MPG, using around 0.13 litres of petrol to cover that mile, so the fuel to travel that distance cost you about 18 pence.

Spending 3 pence to save 6 seconds is equivalent to spending £18 to save 1 hour. The average median wage in the UK is far lower than £18 an hour (currently, it’s £12.50 per hour for full-time workers (PDF))* – in other words, if you drove at the speed limit to get to/from work, the money you’d be spending on petrol would mean most people would actually lose out (people who car-share would be in a better position, but few people car-share to work).

All the extra pay taken home by workers would simply end up going straight to the petrol companies – and when the government is trying to increase consumer spending, that’s the last thing the economy needs.

(Oops, forgot to mention that this post bears a debt of inspiration to this xkcd comic.)

* Thanks to Lukeablancas in the comments for pointing out that I’ve gone for the median wage. The median wage is good for working out what this means for the average person, since it’s unaffected by extremes, but if we’re looking at the country as a whole, the mean wage might be better – this will take high-earners like company bosses into account, as well as people who work in short but intense shifts, like some freelancers. In 2010, the mean wage for men was £16.00 per hour and for women it was £12.92 per hour (annoyingly the government hasn’t released the combined figures for men and women, but assuming there are roughly equal numbers of both in work the average wage overall is £14.46 per hour). Either way, on average people will end up losing out.

Do they? Well, some of them might, but the research in question wasn’t about rioters at all.

Researchers from the University of Cardiff uncovered a link between impulsiveness and levels of the neurotransmitter GABA in a key brain region.

… Around 30 male university students had their levels of GABA measured using a specialised type of brain scan.

They were also asked to complete questionnaires that assessed different aspects of impulsiveness, a trait known to influence self-control.

Participants with more GABA in the pre-frontal brain region had lower scores for ‘urgency’ – the tendency to behave rashly in response to distress or strong emotions and urges.

There was no connection to rioting in the study. Any connection made in the article is being made by journalists – this article has no by-line, being published solely under the Daily Mail Reporter name, but I think it came from the Press Association originally – and it’s a tenuous connection. You see, The Mail is working completely backwards here – they’ve decided that since people who have less GABA tend to behave more rashly, people who they think behaved rashly must have less GABA. You might as well assume that since every MP is in London right now, everyone in London is an MP.

That’s a graph from the paper, showing the connection between the amount of GABA in one particular part of the brain (along the bottom axis) and how strong the individual’s feeling of urgency was (along the side axis) in two groups (cohorts). There does appear to be a correlation (the R number is a measure of how strong this correlation is; R = -0.7 is a reasonable correlation) but look at the two I’ve highlighted with red dots in cohort 2. These two people have the same amount of GABA in their brains, but one of them was incredibly impulsive while the other was one of the calmest people in the study. Likewise, in cohort 1, while there was a definite tendency for people with more GABA to be less impulsive, just look at that cluster of dots – there are impulsive people with lots of GABA, and cautious people without it.

The best you could possibly say about this article is that maybe on average a rioter* has less GABA than normal, assuming these riots are entirely impulsive and there is nothing at all planned or premeditated about them. But then, why does this study need to be connected to riots at all? The paper came out in July before the riots, it’s not about riots – or any kind of violence at all – and none of the scientists quoted mention them, and to be honest, blaming the riots entirely on brain chemistry leaves a nasty taste in my mouth. As Mindhacks has pointed out, The Daily Mail seems to be going to great lengths to avoid exploring any of the context behind the riots, and this kind of story helps bolster the Mail‘s line that there is no deeper cause of these riots than “criminality pure and simple”.

* Male rioters at least – the study only looked at men, so there’s no guarantee this correlation is true in women too.

Edit: The researchers behind the study have published a scathing rebuttal in The Guardian, saying “Let us be absolutely clear. Our research has almost nothing to say about rioting, and certainly can’t be used to justify or excuse any type of behaviour.” Despite complaints from the scientists, The Mail‘s article is still online.

Indeed, admixed embryo research was so secretive that it only got a few thousand column inches from tiny obscure outlets like The Times, the BBC and, err, The Mail.

That said, the stupidest thing in the article is not The Mail‘s coverage, which overall isn’t as terrible as I thought it would be*, though there’s no attempt at explaining the issues beyond just quoting a spokesperson from each side, and it doesn’t make clear that a lot of the experiments in question – implanting a human nucleus into an empty animal cell – don’t make “hybrids” (more strictly, chimeras or admixed embryos) at all; they just make what is for all intents and purposes a human egg cell (taking eggs out of humans naturally is slightly dangerous, so it’s hard to justify putting women at risk for a science experiment when you can just make egg substitutes in the lab).

No, that prize goes to Lord Alton, who first showed the figures to The Mail. He says:

‘Ethically it can never be justifiable – it discredits us as a country. It is dabbling in the grotesque.

‘At every stage the justification from scientists has been: if only you allow us to do this, we will find cures for every illness known to mankind. This is emotional blackmail.

And those cancer scientists asking for money to invent drugs that cure cancer! Pah! Terrible! It’s emotional blackmail, that’s what it is.

Still, if you’re going to ban scientists from using “curing disease” as a justification then I guess it is pretty hard to justify.

‘Of the 80 treatments and cures which have come about from stem cells, all have come from adult stem cells – not embryonic ones.

‘On moral and ethical grounds this fails; and on scientific and medical ones too.’

I’m not sure where he got that awfully precise figure of 80 from. But yes, all currently approved stem cell treatments have from adult stem cells… because adult stem research has been going strong for over 30 years while embryonic stem cell research is far more recent and has had a troubled history (especially in America); the first embryonic stem cell treatments are just starting to be tested. If in 5 or 10 years there are still no working embryonic stem cell treatments, then it will be time to look at whether embryo research is the best route to take. Right now, though, it’s much too early to say whether this fails scientifically.

New figures show that under Labour the state was happy to pay your way, no questions asked.

Those claiming Disability Living Allowance soared from 2.1million in 2000 to 3.1million last year. The annual cost is now £12billion.

So, 3.1 million have “taken the rest of their working lives off” on Disability Living Allowance, and the state is “paying their way”? Well, no.

Disability Living Allowance is a supplementary payment, given to people with disabilities, which helps cover their care and mobility costs – in The Sun‘s case, they seem to be talking solely about the part of the DLA that covers care, since that’s where the 3.1 million figure comes from. There are different levels of DLA, depending on how severe the disability is, but even in the most severe case – someone who requires 24 hour care – the recipient would only get £73.60 a week, or about £3,800 a year, and on average, people only receive about £46.30 a week, or £2,400 a year (and 500,000 of that 3.1 million get nothing at all). No-one has “taken the rest of their working lives off” to live on £2,400 a year.

Incidentally, that part about the annual cost being £12 billion does seem to be including the cost of mobility allowance as well – the cost of the care part of the DLA is only £6.4 billion a year. It sounds like a lot, but like I say, it only actually works out at about £46 per person per week – not very much at all when you think about the cost of a private carer, or the earnings lost by a friend or family member who takes time off work to provide care.

Clearly The Sun must realise this – they complain that “Many of those handed up to £73.60 a week are laid low with ailments such as “alcohol abuse” or allergies“, clearly hoping that we won’t realise that £73.60 is not all that much money. There maybe people on DLA because of alcohol abuse or allergies, but in that case, it will be because their condition is so serious that they need part-or-full-time care. To qualify for even the lowest rate, you need to be either physically unable to cook for yourself or require care for part of the day. That’s more than just “someone who cannot get out of bed because their hangover is so bad“.

The Sun also says that “The vast majority of claimants have never been medically assessed“, which also isn’t true. Most people aren’t assessed by the Department of Work and Pensions, true, but in order to qualify for DLA, you need to have been diagnosed by your doctor. Everyone who is on DLA was assessed by their doctor.

Now at last the Government plans to order regular assessments to weed out the workshy.

It should make the economy look healthier by a few billion pounds a year.

Edit: The Express’s coverage is more or less the same, but with TPA quotes and the added bonus that they express incredulity that people with back pain might have trouble moving around. WHO’D HAVE THOUGHT?

(The Sun discards its “Sun Says” columns each day. I’ve preserved this one beneath the fold)